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These findings, which are discussed, showed that stroke index (SI = V.SL) could be used as a sensitive criterion to assess the swimmer with a disability in relationship to his classification level.

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We studied in the field the load transport behavior of workers of the polymorphic Mediterranean seed harvester ant Messor barbarus. Individual ants used two different methods to transport food items: carrying and dragging. The probability of dragging instead of carrying varied significantly with both the mass of the item transported and its linear dimension. Moreover, the values of item mass and length at which dragging began to occur increased with increasing size of the workers. However, larger ants began dragging at decreasing values of the relative mass represented by the items transported, which reflects different biomechanical constraints resulting from allometric relationships between the different parts of their body. Transport rate was significantly higher in large ants but varied in the same way for workers of different sizes with the relative mass of the item transported. Nevertheless, although large ants were individually more efficient than small ants in transporting food items, the relative transport rate, defined as the ratio of transport rate to the mass of the ant, was higher for small ants than for large ants. Colonies should thus have a greater benefit in investing in small ants than in large ants for the transport of food items. This may explain why the proportion of large ants is so small on the foraging columns of M. barbarus and why large ants are most often employed in colonies for tasks other than transporting food items.

The purpose of the study was to establish the link between the saddle vertical force and its determinants in order to establish the strategies that could trigger the sit-stand transition. We hypothesized that the minimum saddle vertical force would be a critical parameter influencing the sit-stand transition during cycling. Twenty-five non-cyclists were asked to pedal at six different power outputs from 20% (1.6 ± 0.3 W kg(-1)) to 120% (9.6 ± 1.6 W kg(-1)) of their spontaneous sit-stand transition power obtained at 90 rpm. Five 6-component sensors (saddle tube, pedals and handlebars) and a full-body kinematic reconstruction were used to provide the saddle vertical force and other force components (trunk inertial force, hips and shoulders reaction forces, and trunk weight) linked to the saddle vertical force. Minimum saddle vertical force linearly decreased with power output by 87% from a static position on the bicycle (5.30 ± 0.50 N kg(-1)) to power output=120% of the sit-stand transition power (0.68 ± 0.49 N kg(-1)). This decrease was mainly explained by the increase in instantaneous pedal forces from 2.84 ± 0.58 N kg(-1) to 6.57 ± 1.02 N kg(-1) from 20% to 120% of the power output corresponding to the sit-stand transition, causing an increase in hip vertical forces from -0.17 N kg(-1) to 3.29 N kg(-1). The emergence of strategies aiming at counteracting the elevation of the trunk (handlebars and pedals pulling) coincided with the spontaneous sit-stand transition power. The present data suggest that the large decrease in minimum saddle vertical force observed at high pedal reaction forces might trigger the sit-stand transition in cycling.

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The purpose of the present study was to submit disabled swimmers to two maximal swimming tests, and by comparing the physiological and performance responses of disabled and normal swimmers to determine if these adapted tests can be used to design training programmes for this particular class of swimmer. Two groups of disabled (n = 8 and 6) and two groups of normal competitive swimmers (n = 9 and 13) were respectively submitted to a functional maximal aerobic power test (FMAPT) and a maximal anaerobic lactic test (MANLT). For the disabled, the FMAPT included a slower initial speed and a slower increase in swimming speeds. In the maximal aerobic test, exercise duration, peak heart rate, and the maximal speed relative to the respective best time of a 100-m race [55.5 (SD 3.9) compared to 56.5 (SD 2.8)%] were not significantly different between the disabled and normal swimmers. Peak lactate concentration was, however, higher in the disabled swimmers [10.8 (SD 3.5) compared to 6.8 (SD 1.6)mmol.l-1]. In the MNALT, peak lactate concentration [14.3 (SD 4) compared to 16.8 (SD 1.9)mmol.l-1], and the maximal speed relative to the respective best time in a 100-m race [99.1 (SD 3.2) compared to 98.3 (SD 2.5)%] were not significantly different between the disabled and normal swimmers. These results would seem to indicate that functional maximal aerobic and anaerobic field tests could be used to evaluate and design training programmes for disabled competitive swimmers.